Measurements in the wireless
|
|
- Stephany Walker
- 6 years ago
- Views:
Transcription
1 Contents Measurements in the wireless Lecture slides for S Mika Ilvesmäki Motivation Wireless environment spesifics Wireless trace collection Wireless measurement methods Mobility measurements Networking laboratory Goals of this lecture After this lecture you should Know how to characterize the wireless environment in regards to measurements Know why measurements in the wireless are hard and how the gathering of measurement information is distributed Know where the wireline and wireless measurements and analysis are the same and where they differ Why measure? Wireless networks differ from the usual Internet access The access is (slightly) spatially dynamic Ad-hoc networking is easier Lack of wiring (=wireless) can create very highly populated networks Medium (the air interface) access is more complex and dynamic Clients and applications may show much more diversity 1
2 The same ol same ol Wireless networks contain the same users with same applications as networks in the wireline However, there might also be (a significant amount of) legacy customers from mobile voice networks (GSM). Same measurements and and analysis apply on layers 3 and above Same results definitely do not! Due to access layer being slightly different also the results may turn out to be slightly different Network traffic properties as a function of layer 2?! What is different? A network is a network However, WLAN performance is influenced 1. Mobility Handoff, handover 2. Channel noise 2,4/5GHz area is unlicensed, noise may be a problem with increased distance 3. Multiple access contention Access quality decreases as user count increases Measurements in layers 1 and 2 Transmission rates, retransmissions, signal strength Collision avoidance, detection RTS/CTS Traffic in different channels Wireless traces Incomplete Different depending on the measurement point Design is distributed, control points do not exist Inaccurate due to more probable configuration errors Subject to layer 2 features Contention very much dependent on where the measurement point is located and how it is moving (mobility) Channel usage and contention is location-dependent 2
3 Trace collection methods - nodes Wireless monitors Monitor all activity in the channels Event-triggered logs Memory and storage requirements Form a view (analysis!) of the network status and notify Other nodes in the WLAN Access point(s) Information/state distribution uses up bandwidth Careful planning and management of the measurement arrangements Do not overload production networks Do not lose relevan information Trace collection methods - BS Network trace dumps at the base station Poll access points with SNMPprotocol Gather info on amounts of connected users, transmission errors, and transmitted traffic Trace collection methods - Core Network trace dumps at aggregating routers Where traffic from several access points is aggregated Capture also traffic directed to WLANs Addtional monitoring and capturing load Determine traffic mix, network service profile etc. Normal traffic analysis Packet loss Two sources for packet loss Competing transimissions Miscalculation in power management Insufficient signal strength Probing for bandwidth Available BW depends on Amount of users in the coverage area Overall traffic load Available BW varies a lot Actively probing for BW introduces additional traffic and interferes with other traffic 3
4 Unintrusive bandwidth probing Configure dedicated queues for probe packets Forward probe packets only if no other traffic exists Larger packets/lower bandwidth still cause some interference to other traffic Egress router measures the packet arrivals and sends the info back to the sender Losses in wireless High error/loss rates Competing transmissions Signal strength related losses Adaptive transmission rates result in busier medium A lot of time data is sent at 1Mbps -> medium is reserved and contented and more losses/errors occur Multi-path fading produces a lot of (bit) errors Packets/bits received multiple times Packet delay WLANs produce larger transport delays Signal propagation (not that large contributor) Aggregating signal propagation results is significant delay Handovers Retransmissions Inference Jitter in wireless Due to medium dynamics jitter is much more pronounced in wireless Handovers Inferences, shadowing Link Layer Scheduling RTS/CTS 4
5 Measuring for mobility How often and how much a user moves while on line Physical movements are hard to measure RFIDs, but way-y in the future Detect roaming patterns from APs With dense AP placement, the node may change APs even if it is not moving Group APs into location clusters (per building, for instance) Mobility measures Time spent in one AP (location cluster) Movement speed (Mobile) session duration And visited APs in that time Application profile relation to movement Handoff measurements Handoff is performed when a mobile node transfers from one AP to another. Hand-off time is divided into two components Inter-cell time (rendezvouz-time), the time elapsed moving from one APs range to another In a well planned network this time should be negligible Hand-off setup time The time required to restore traffic flow when APs have changed Routing measurements in wireless Wireless environments are dynamic Especially ad-hoc networks Dynamic/Adaptive routing is mandatory Routing table sizes Rate of changes in the routing table Modeling Convergence times / dynamism of the network Modeling 5
6 Results from previous measurements High overhead Results show that only 40% of traffic is original data packets Retransmissions, acknowledgements, management traffic Retransmission rates are high (28% of data, 46% of data transmission time) Design for location access, not complete coverage Make sure you have APs where the users are, but not necessarily on the way to get there Users seem not to be moving when using WLANs Open&interesting issues User mobility modeling How do users move and how to model it? Inference studies with varying network topology More studies in wireless environments needed Application behavior in WLAN, 3G environments Overall traffic profiling and analysis This lecturer has no knowledge of analysis performed, for instance, in Aalto-network at TKK. Sell the idea, secure funding and get a summer/m.sc. Thesis job!! Ad Hoc networks will produce interesting analysis targets Summary of wireless/mobility measurements Several methods of gathering the traces No single method provides complete overview of the network status User profiling and characterization is twice as hard In addition to application usage there is also user mobility to account for Networks are also dynamic Mobile nodes, dynamic routing Distributed network status In nodes, APs and aggregate routers Several factors in various layers effect the network status Wireless network analysis is challenging No easy conclusions, no easy analysis 6
Multiple Access in Cellular and Systems
Multiple Access in Cellular and 802.11 Systems 1 GSM The total bandwidth is divided into many narrowband channels. (200 khz in GSM) Users are given time slots in a narrowband channel (8 users) A channel
More informationComputer Communication III
Computer Communication III Wireless Media Access IEEE 802.11 Wireless LAN Advantages of Wireless LANs Using the license free ISM band at 2.4 GHz no complicated or expensive licenses necessary very cost
More informationWireless and Mobile Networks 7-2
Wireless and Mobile Networks EECS3214 2018-03-26 7-1 Ch. 6: Wireless and Mobile Networks Background: # wireless (mobile) phone subscribers now exceeds # wired phone subscribers (5-to-1)! # wireless Internet-connected
More informationMobile and Sensor Systems
Mobile and Sensor Systems Lecture 2: Mobile Medium Access Control Protocols and Wireless Systems Dr Cecilia Mascolo In this lecture We will describe medium access control protocols and wireless systems
More informationECE 4450:427/527 - Computer Networks Spring 2017
ECE 4450:427/527 - Computer Networks Spring 2017 Dr. Nghi Tran Department of Electrical & Computer Engineering Lecture 5.6: Wireless Networks - MAC Dr. Nghi Tran (ECE-University of Akron) ECE 4450:427/527
More informationUniversity of Würzburg Institute of Computer Science Research Report Series. Performance Comparison of Handover Mechanisms in Wireless LAN Networks
University of Würzburg Institute of Computer Science Research Report Series Performance Comparison of Handover Mechanisms in Wireless LAN Networks Rastin Pries and Klaus Heck Report No. 339 September 2004
More information15-441: Computer Networking. Wireless Networking
15-441: Computer Networking Wireless Networking Outline Wireless Challenges 802.11 Overview Link Layer Ad-hoc Networks 2 Assumptions made in Internet Host are (mostly) stationary Address assignment, routing
More informationTopic 2b Wireless MAC. Chapter 7. Wireless and Mobile Networks. Computer Networking: A Top Down Approach
Topic 2b Wireless MAC Chapter 7 Wireless and Mobile Networks Computer Networking: A Top Down Approach 7 th edition Jim Kurose, Keith Ross Pearson/Addison Wesley April 2016 7-1 Ch. 7: Background: # wireless
More informationWireless Networks. CSE 3461: Introduction to Computer Networking Reading: , Kurose and Ross
Wireless Networks CSE 3461: Introduction to Computer Networking Reading: 6.1 6.3, Kurose and Ross 1 Wireless Networks Background: Number of wireless (mobile) phone subscribers now exceeds number of wired
More informationSpectrum Management in Cognitive Radio Networks
Spectrum Management in Cognitive Radio Networks Jul 14,2010 Instructor: professor m.j omidi 1/60 BY : MOZHDEH MOLA & ZAHRA ALAVIKIA Contents Overview: Cognitive Radio Spectrum Sensing Spectrum Decision
More informationWiFi Networks: IEEE b Wireless LANs. Carey Williamson Department of Computer Science University of Calgary Winter 2018
WiFi Networks: IEEE 802.11b Wireless LANs Carey Williamson Department of Computer Science University of Calgary Winter 2018 Background (1 of 2) In many respects, the IEEE 802.11b wireless LAN (WLAN) standard
More informationLast Lecture: Data Link Layer
Last Lecture: Data Link Layer 1. Design goals and issues 2. (More on) Error Control and Detection 3. Multiple Access Control (MAC) 4. Ethernet, LAN Addresses and ARP 5. Hubs, Bridges, Switches 6. Wireless
More informationLecture 9. Quality of Service in ad hoc wireless networks
Lecture 9 Quality of Service in ad hoc wireless networks Yevgeni Koucheryavy Department of Communications Engineering Tampere University of Technology yk@cs.tut.fi Lectured by Jakub Jakubiak QoS statement
More informationWireless LANs. ITS 413 Internet Technologies and Applications
Wireless LANs ITS 413 Internet Technologies and Applications Aim: Aim and Contents Understand how IEEE 802.11 wireless LANs work Understand what influences the performance of wireless LANs Contents: IEEE
More informationWireless networks. Wireless Network Taxonomy
Wireless networks two components to be considered in deploying applications and protocols wireless links ; mobile computing they are NOT the same thing! wireless vs. wired links lower bandwidth; higher
More informationMAC in /20/06
MAC in 802.11 2/20/06 MAC Multiple users share common medium. Important issues: Collision detection Delay Fairness Hidden terminals Synchronization Power management Roaming Use 802.11 as an example to
More informationWireless and WiFi. Daniel Zappala. CS 460 Computer Networking Brigham Young University
Wireless and WiFi Daniel Zappala CS 460 Computer Networking Brigham Young University Wireless Networks 2/28 mobile phone subscribers now outnumber wired phone subscribers similar trend likely with Internet
More informationData Communications. Data Link Layer Protocols Wireless LANs
Data Communications Data Link Layer Protocols Wireless LANs Wireless Networks Several different types of communications networks are using unguided media. These networks are generally referred to as wireless
More informationUNIT II NETWORKING
UNIT II INTRODUCTION TO WIRELESS NETWORKING Wireless Network The cellular telephone system is responsible for providing coverage throughout a particular area known as coverage region or market The interconnection
More informationPIE in the Sky : Online Passive Interference Estimation for Enterprise WLANs
WiNGS Labs PIE in the Sky : Online Passive Interference Estimation for Enterprise WLANs * Nokia Research Center, Palo Alto Shravan Rayanchu, Suman Banerjee University of Wisconsin-Madison Konstantina Papagiannaki
More informationChapter 6 Wireless and Mobile Networks
Chapter 6 Wireless and Mobile Networks Computer Networking: A Top Down Approach Featuring the Internet, 3 rd edition. Jim Kurose, Keith Ross Addison-Wesley, July 2004. 6: Wireless and Mobile Networks 6
More informationHomework 1. Question 1 - Layering. CSCI 1680 Computer Networks Fonseca
CSCI 1680 Computer Networks Fonseca Homework 1 Due: 27 September 2012, 4pm Question 1 - Layering a. Why are networked systems layered? What are the advantages of layering? Are there any disadvantages?
More informationCSCD 433 Network Programming Fall Lecture 7 Ethernet and Wireless
CSCD 433 Network Programming Fall 2016 Lecture 7 Ethernet and Wireless 802.11 1 Topics 802 Standard MAC and LLC Sublayers Review of MAC in Ethernet MAC in 802.11 Wireless 2 IEEE Standards In 1985, Computer
More informationFinal Exam: Mobile Networking (Part II of the course Réseaux et mobilité )
Final Exam: Mobile Networking (Part II of the course Réseaux et mobilité ) Prof. J.-P. Hubaux February 12, 2004 Duration: 2 hours, all documents allowed Please write your answers on these sheets, at the
More information6.9 Summary. 11/20/2013 Wireless and Mobile Networks (SSL) 6-1. Characteristics of selected wireless link standards a, g point-to-point
Chapter 6 outline 6.1 Introduction Wireless 6.2 Wireless links, characteristics CDMA 6.3 IEEE 802.11 wireless LANs ( wi-fi ) 6.4 Cellular Internet Access architecture standards (e.g., GSM) Mobility 6.5
More informationData Communication & Networks G Session 5 - Main Theme Wireless Networks. Dr. Jean-Claude Franchitti
Data Communication & Networks G22.2262-001 Session 5 - Main Theme Wireless Networks Dr. Jean-Claude Franchitti New York University Computer Science Department Courant Institute of Mathematical Sciences
More informationWireless Challenges : Computer Networking. Overview. Routing to Mobile Nodes. Lecture 25: Wireless Networking
Wireless Challenges 15-441: Computer Networking Lecture 25: Wireless Networking Force us to rethink many assumptions Need to share airwaves rather than wire Don t know what hosts are involved Host may
More informationOutline: Connecting Many Computers
Outline: Connecting Many Computers Last lecture: sending data between two computers This lecture: link-level network protocols (from last lecture) sending data among many computers 1 Review: A simple point-to-point
More informationShared Access Networks Wireless. 1/27/14 CS mywireless 1
Shared Access Networks Wireless 1 Wireless and Mobile Networks Background: # wireless (mobile) phone subscribers now exceeds # wired phone subscribers (5-to-1)! # wireless Internet-connected devices equals
More informationLecture 16: QoS and "
Lecture 16: QoS and 802.11" CSE 123: Computer Networks Alex C. Snoeren HW 4 due now! Lecture 16 Overview" Network-wide QoS IntServ DifServ 802.11 Wireless CSMA/CA Hidden Terminals RTS/CTS CSE 123 Lecture
More information4.3 IEEE Physical Layer IEEE IEEE b IEEE a IEEE g IEEE n IEEE 802.
4.3 IEEE 802.11 Physical Layer 4.3.1 IEEE 802.11 4.3.2 IEEE 802.11b 4.3.3 IEEE 802.11a 4.3.4 IEEE 802.11g 4.3.5 IEEE 802.11n 4.3.6 IEEE 802.11ac,ad Andreas Könsgen Summer Term 2012 4.3.3 IEEE 802.11a Data
More informationMobile Communications Chapter 7: Wireless LANs
Characteristics IEEE 802.11 PHY MAC Roaming IEEE 802.11a, b, g, e HIPERLAN Bluetooth Comparisons Prof. Dr.-Ing. Jochen Schiller, http://www.jochenschiller.de/ MC SS02 7.1 Comparison: infrastructure vs.
More informationMohammad Hossein Manshaei 1393
Mohammad Hossein Manshaei manshaei@gmail.com 1393 Wireless Links, WiFi, Cellular Internet Access, and Mobility Slides derived from those available on the Web site of the book Computer Networking, by Kurose
More informationWireless TCP Performance Issues
Wireless TCP Performance Issues Issues, transport layer protocols Set up and maintain end-to-end connections Reliable end-to-end delivery of data Flow control Congestion control Udp? Assume TCP for the
More informationCSC 4900 Computer Networks: Wireless Networks
CSC 4900 Computer Networks: Wireless Networks Professor Henry Carter Fall 2017 Last Time Mobile applications are taking off! What about current platforms is fueling this? How are an application s permission
More informationMSIT 413: Wireless Technologies Week 8
MSIT 413: Wireless Technologies Week 8 Michael L. Honig Department of EECS Northwestern University November 2017 The Multiple Access Problem How can multiple mobiles access (communicate with) the same
More informationMultiple Access Links and Protocols
Multiple Access Links and Protocols Two types of links : point-to-point PPP for dial-up access point-to-point link between Ethernet switch and host broadcast (shared wire or medium) old-fashioned Ethernet
More informationCWNP PW Certified Wireless Analysis Professional. Download Full Version :
CWNP PW0-270 Certified Wireless Analysis Professional Download Full Version : http://killexams.com/pass4sure/exam-detail/pw0-270 QUESTION: 50 ABC Company is having VoWiFi latency problems on their 802.11g
More informationTelecommunication Services Engineering Lab. Roch H. Glitho
1 Congestion handling in wired TCP: Detailed treatment 1. - Fundamental assumptions and principles - Key parameters - Slow start - Congestion avoidance - Fast re-transmit and fast recovery 2 Fundamental
More informationGetting Connected (Chapter 2 Part 4) Networking CS 3470, Section 1 Sarah Diesburg
Getting Connected (Chapter 2 Part 4) Networking CS 3470, Section 1 Sarah Diesburg Five Problems Encoding/decoding Framing Error Detection Error Correction Media Access Five Problems Encoding/decoding Framing
More informationstandard. Acknowledgement: Slides borrowed from Richard Y. Yale
802.11 standard Acknowledgement: Slides borrowed from Richard Y. Yang @ Yale IEEE 802.11 Requirements Design for small coverage (e.g. office, home) Low/no mobility High data rate applications Ability to
More informationModule 6: Wireless Mobile Networks
Module 6: Wireless Mobile Networks SMD123 Computer Communications Kaustubh Phanse Department of Computer Science and Electrical Engineering Luleå University of Technology Lecture Objectives Wireless links
More informationData and Computer Communications. Chapter 13 Wireless LANs
Data and Computer Communications Chapter 13 Wireless LANs Wireless LAN Topology Infrastructure LAN Connect to stations on wired LAN and in other cells May do automatic handoff Ad hoc LAN No hub Peer-to-peer
More informationWireless and Mobile Networks
Wireless and Mobile Networks Raj Jain Washington University in Saint Louis Saint Louis, MO 63130 Jain@wustl.edu Audio/Video recordings of this lecture are available on-line at: http://www.cse.wustl.edu/~jain/cse473-11/
More informationAn efficient trigger to improve intra-wifi handover performance
An efficient trigger to improve intra-wifi handover performance Roberta Fracchia, Guillaume Vivier Motorola Labs, Parc les Algorithmes, Saint-Aubin, 91193 Gif-sur-Yvette, France Abstract Seamless mobility
More informationSample Solution to Problem Set 3
College of Computer & Information Science Fall 2007 Northeastern University Handout 6 CSG250: Wireless Networks 25 October 2007 Sample Solution to Problem Set 3 (The problem numbers from the text are the
More informationM06:Wireless and Mobile Networks. Corinna Schmitt
M06:Wireless and Mobile Networks Corinna Schmitt corinna.schmitt@unibas.ch Acknowledgement 2016 M06 2 Background q # wireless (mobile) phone subscribers now exceeds # wired phone subscribers (5-to-1)!
More informationAdvanced Computer Networks WLAN
Advanced Computer Networks 263 3501 00 WLAN Patrick Stuedi Spring Semester 2014 1 Oriana Riva, Department of Computer Science ETH Zürich Last week Outlook Medium Access COPE Short Range Wireless Networks:
More informationCSCI-1680 Wireless Chen Avin
CSCI-1680 Wireless Chen Avin Based on slides from Computer Networking: A Top Down Approach - 6th edition Administrivia TCP is due on Friday Final Project is out (fun, two weeks) Wireless and Mobile Networks
More informationChapter 7. Basic Wireless Concepts and Configuration. Part I
Chapter 7 Basic Wireless Concepts and Configuration Part I CCNA3-1 Chapter 7-1 Note for Instructors These presentations are the result of a collaboration among the instructors at St. Clair College in Windsor,
More informationLocal Area Networks NETW 901
Local Area Networks NETW 901 Lecture 4 Wireless LAN Course Instructor: Dr.-Ing. Maggie Mashaly maggie.ezzat@guc.edu.eg C3.220 1 Contents What is a Wireless LAN? Applications and Requirements Transmission
More informationCS 348: Computer Networks. - WiFi (contd.); 16 th Aug Instructor: Sridhar Iyer IIT Bombay
CS 348: Computer Networks - WiFi (contd.); 16 th Aug 2012 Instructor: Sridhar Iyer IIT Bombay Clicker-1: Wireless v/s wired Which of the following differences between Wireless and Wired affect a CSMA-based
More informationCARA: Collision-Aware Rate Adaptation for IEEE WLANs. Presented by Eric Wang
CARA: Collision-Aware Rate Adaptation for IEEE 802.11 WLANs Presented by Eric Wang 1 Outline Introduction Related Work Preliminaries CARA Performance Evaluation Conclusion and Future Work 2 Basic CSMA/CA
More informationCSMC 417. Computer Networks Prof. Ashok K Agrawala Ashok Agrawala. Fall 2018 CMSC417 Set 1 1
CSMC 417 Computer Networks Prof. Ashok K Agrawala 2018 Ashok Agrawala Fall 2018 CMSC417 Set 1 1 The Medium Access Control Sublayer November 18 Nov 6, 2018 2 Wireless Networking Technologies November 18
More informationDouble-Loop Receiver-Initiated MAC for Cooperative Data Dissemination via Roadside WLANs
Double-Loop Receiver-Initiated MAC for Cooperative Data Dissemination via Roadside WLANs Presented by: Hao Liang Broadband Communications Research (BBCR) Lab 2012.7.6 Outline Introduction and Related Work
More informationLecture 12 December 04, Wireless Access. Graduate course in Communications Engineering. University of Rome La Sapienza. Rome, Italy
Lecture 12 December 04, 2017 Wireless Access Graduate course in Communications Engineering University of Rome La Sapienza Rome, Italy 2017-2018 Random Medium Access Control Part II - CSMA and Collision
More informationMobile & Wireless Networking. Lecture 7: Wireless LAN
192620010 Mobile & Wireless Networking Lecture 7: Wireless LAN [Schiller, Section 7.3] [Reader, Part 6] [Optional: "IEEE 802.11n Development: History, Process, and Technology", Perahia, IEEE Communications
More informationAirMagnet Wireless LAN Design
AirMagnet Wireless LAN Design Source: AirMagnet Survey Pro + Spectrum XT Tom Woodyer Senior Product Specialist APAC Q3, 2010 Todays agenda. Understand the media Wireless Network Basics Types of Wireless
More informationEvaluating VoIP using Network Simulator-2
Athens University of Economic and Business Evaluating VoIP using Network Simulator-2 June 2007 Author: Papantonakos Manos Supervisor Prof.: George Xylomenos Co-Supervisor Prof: George Polyzos About WiMax
More informationChapter 5 Ad Hoc Wireless Network. Jang Ping Sheu
Chapter 5 Ad Hoc Wireless Network Jang Ping Sheu Introduction Ad Hoc Network is a multi-hop relaying network ALOHAnet developed in 1970 Ethernet developed in 1980 In 1994, Bluetooth proposed by Ericsson
More informationLecture 4: Wireless MAC Overview. Hung-Yu Wei National Taiwan University
Lecture 4: Wireless MAC Overview Hung-Yu Wei National Taiwan University Medium Access Control Topology 3 Simplex and Duplex 4 FDMA TDMA CDMA DSSS FHSS Multiple Access Methods Notice: CDMA and spread spectrum
More informationINTRODUCTION TO WIRELESS LAN, MAC PROTOCOLS and INTERFERENCE. Choong Seon Hong, KHU
INTRODUCTION TO WIRELESS LAN, MAC PROTOCOLS and INTERFERENCE cshong@khu.ac.kr, Choong Seon Hong, KHU Outline 2 Introduction Wireless LAN Architecture Wireless LAN standards Media Access Problem The IEEE
More informationFull file at
ch02 True/False Indicate whether the statement is true or false. 1. The number of nodes on a network and the length of cable used influence the quality of communication on the network. 2. Repeaters and
More informationWireless technology Principles of Security
Wireless technology Principles of Security 1 Wireless technologies 2 Overview This module provides an introduction to the rapidly evolving technology of wireless LANs (WLANs). WLANs redefine the way the
More informationAnnouncements / Wireless Networks and Applications Lecture 9: Wireless LANs Wireless. Regular Ethernet CSMA/CD.
Announcements 18-452/18-750 Wireless Networks and Applications Lecture 9: Wireless LANs 802.11 Wireless Peter Steenkiste Homework 1 should be out by tomorrow Project 1 by Friday Schedule:» Thursday lecture
More informationWireless and Mobile Networks Reading: Sections 2.8 and 4.2.5
Wireless and Mobile Networks Reading: Sections 2.8 and 4.2.5 Acknowledgments: Lecture slides are from Computer networks course thought by Jennifer Rexford at Princeton University. When slides are obtained
More informationEfficient Transmission of H.264 Video over WLANs
Efficient Transmission of H.264 Video over WLANs Yaser P. Fallah March 2007 UBC 1 Multimedia Communications Multimedia applications are becoming increasingly popular Video on mobile devices (cell phones,
More informationDepartment of Electrical and Computer Systems Engineering
Department of Electrical and Computer Systems Engineering Technical Report MECSE-6-2006 Medium Access Control (MAC) Schemes for Quality of Service (QoS) provision of Voice over Internet Protocol (VoIP)
More informationVertical and Horizontal Handover in Heterogeneous Wireless Networks using OPNET
Vertical and Horizontal Handover in Heterogeneous Wireless Networks using OPNET Abhishek Dhiman M.E, E.C.E Department, Thapar University, Patiala Karamjit Singh Sandha Asst. Professor, E.C.E Department
More informationLAB PROJECT Nº1 1 INTRODUCTION REDES MÓVEIS E SEM FIOS , MEEC PERFORMANCE OF WIRELESS PERSONAL AREA NETWORKS
LAB PROJECT Nº1 REDES MÓVEIS E SEM PERFORMANCE OF WIRELESS PERSONAL AREA NETWORKS 1 INTRODUCTION The performance of wireless networks is highly dependent of physical phenomena, such as path loss, shadowing,
More informationMohamed Khedr.
Mohamed Khedr http://webmail.aast.edu/~khedr Tentatively Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15 Overview Packet Switching IP addressing
More informationQos support and adaptive video
Qos support and adaptive video QoS support in ad hoc networks MAC layer techniques: 802.11 e - alternation of contention based and contention free periods; differentiated (per class) Interframe Spacing
More informationNo lecture on Thurs. Last homework will be out this week (not due, covers wireless) Extra office hours for next week and the week after.
Administrivia No lecture on Thurs. Last homework will be out this week (not due, covers wireless) Extra office hours for next week and the week after. 1 CSMA/CA: Recap Sensing in wireless medium is limited
More informationSubject: Adhoc Networks
ISSUES IN AD HOC WIRELESS NETWORKS The major issues that affect the design, deployment, & performance of an ad hoc wireless network system are: Medium Access Scheme. Transport Layer Protocol. Routing.
More informationWireless Challenges and Resolutions
Wireless Challenges and Resolutions 1 Steven Shelton Senior Network Engineer Oak Ridge National Laboratory Oak Ridge, Tennessee ows@ornl.gov 2 Wireless Challenges and Resolutions Sections Common Problems
More informationAdvanced Computer Networks. WLAN, Cellular Networks
Advanced Computer Networks 263 3501 00 WLAN, Cellular Networks Patrick Stuedi Spring Semester 2013 Oriana Riva, Department of Computer Science ETH Zürich Last week Medium Access COPE Today Last week Short
More informationComputer Networks. Wireless and Mobile Networks. László Böszörményi Computer Networks Mobile - 1
Computer Networks Wireless and Mobile Networks László Böszörményi Computer Networks Mobile - 1 Background Number of wireless (mobile) phone subscribers now exceeds number of wired phone subscribers! Computer
More informationICE 1332/0715 Mobile Computing (Summer, 2008)
ICE 1332/0715 Mobile Computing (Summer, 2008) Medium Access Control Prof. Chansu Yu http://academic.csuohio.edu/yuc/ Simplified Reference Model Application layer Transport layer Network layer Data link
More informationDepartment of EECS - University of California at Berkeley EECS122 - Introduction to Communication Networks - Spring 2005 Final: 5/20/2005
Name: SID: Department of EECS - University of California at Berkeley EECS122 - Introduction to Communication Networks - Spring 2005 Final: 5/20/2005 There are 10 questions in total. Please write your SID
More informationNetwork+ Guide to Networks 6 th Edition. Chapter 8 Wireless Networking
Network+ Guide to Networks 6 th Edition Chapter 8 Wireless Networking Objectives Explain how nodes exchange wireless signals Identify potential obstacles to successful wireless transmission and their repercussions,
More informationOverview : Computer Networking. Spectrum Use Comments. Spectrum Allocation in US Link layer challenges and WiFi WiFi
Overview 15-441 15-441: Computer Networking 15-641 Lecture 21: Wireless Justine Sherry Peter Steenkiste Fall 2017 www.cs.cmu.edu/~prs/15-441-f17 Link layer challenges and WiFi WiFi Basic WiFi design Some
More informationAnnouncements: ECE/CS 372 introduction to computer networks. Assign 4 is due this Thursday Lab 4 is due next Tuesday Assignment 5 posted soon
ECE/CS 372 introduction to computer networks Lecture 14 Announcements: Assign 4 is due this Thursday Lab 4 is due next Tuesday Assignment 5 posted soon Credit for lecture slides to Professor Bechir Hamdaoui
More informationIEEE WLANs (WiFi) Part II/III System Overview and MAC Layer
IEEE 802.11 WLANs (WiFi) Part II/III System Overview and MAC Layer Design goals for wireless LANs (WLANs) Global, seamless operation Low power for battery use No special permissions or licenses needed
More informationReview. Error Detection: CRC Multiple access protocols. LAN addresses and ARP Ethernet. Slotted ALOHA CSMA/CD
Review Error Detection: CRC Multiple access protocols Slotted ALOHA CSMA/CD LAN addresses and ARP Ethernet Some slides are in courtesy of J. Kurose and K. Ross Overview Ethernet Hubs, bridges, and switches
More informationTopics for Today. More on Ethernet. Wireless LANs Readings. Topology and Wiring Switched Ethernet Fast Ethernet Gigabit Ethernet. 4.3 to 4.
Topics for Today More on Ethernet Topology and Wiring Switched Ethernet Fast Ethernet Gigabit Ethernet Wireless LANs Readings 4.3 to 4.4 1 Original Ethernet Wiring Heavy coaxial cable, called thicknet,
More informationConfiguring RF Profiles
Prerequisites for, page 1 Restrictions for, page 1 Information About RF Profiles, page 2 Configuring an RF Profile (GUI), page 5 Configuring an RF Profile (CLI), page 6 Applying an RF Profile to AP Groups
More informationLecture 6. Reminder: Homework 2, Programming Project 2 due on Thursday. Questions? Tuesday, September 13 CS 475 Networks - Lecture 6 1
Lecture 6 Reminder: Homework 2, Programming Project 2 due on Thursday. Questions? Tuesday, September 13 CS 475 Networks - Lecture 6 1 Outline Chapter 2 - Getting Connected 2.1 Perspectives on Connecting
More informationReview For Exam 2. Internetworking. Summary Questions. School of Business Eastern Illinois University. School of Business Eastern Illinois University
School of Business Review For Exam 2 Wednesday 10/6/2004) Abdou Illia, Fall 2004 School of Business Internetworking 3 1. Name the two most known Medium Access Control Protocols found in LANs. How they
More informationRequirements for the Operations & Management of 4G Networks
Requirements for the Operations & Management of 4G Networks Prof. James Won-Ki Hong Dept. of Computer Science and Engineering, Korea & Prof. Alberto Leon-Garcia Dept. of Electrical and Computer Engineering
More informationMobility Management usually includes two parts: location management and handoff management.
Mobile Data / Mobility Management I. Mobile Data Services/ Management This broad area involves a lot of industrial applications. Mobile data services/ management is becoming another profitable market for
More informationQoS issues in Wi-Fi-WMM based triple play home networks
QoS issues in Wi-Fi-WMM based triple play home networks Yun Tao Shi Jean-Marie Bonnin Gilles Straub Thomson, France INRIA/IRISA, France Thomson, France yun-tao.shi@thomson.net jm.bonnin@enst-bretagne.fr
More informationETSN01 Exam. August 22nd am 1pm. Clearly label each page you hand in with your name and the page number in the bottom right hand corner.
ETSN01 Exam August 22nd 2015 8am 1pm Instructions Clearly label each page you hand in with your name and the page number in the bottom right hand corner. Materials allowed: calculator, writing material.
More informationWireless Security Background
Wireless Security Background Wireless Networks The need for mobile computing Laptops, PDAs, Bluetooth devices Smart phones Enabling technology Wireless communication Two important characteristics Wireless
More informationCPSC 826 Internetworking. Wireless and Mobile Networks. Wireless Networks Wireless Hosts
1 CPSC 826 Intering Wireless and Mobile Networks Michele Weigle Department of Computer Science Clemson University mweigle@cs.clemson.edu November 29, 200 Wireless and Mobile Networks Background Number
More informationAnalysis of Variation in IEEE802.11k Channel Load Measurements for Neighbouring WLAN Systems
Analysis of Variation in IEEE802.11k Channel Load Measurements for Neighbouring WLAN Systems Christina THORPE 1, Sean MURPHY, Liam MURPHY School of Computer Science and Informatics, University College
More informationIntroduction to Networking Devices
Introduction to Networking Devices Objectives Explain the uses, advantages, and disadvantages of repeaters, hubs, wireless access points, bridges, switches, and routers Define the standards associated
More informationChapter - 1 INTRODUCTION
Chapter - 1 INTRODUCTION Worldwide Interoperability for Microwave Access (WiMAX) is based on IEEE 802.16 standard. This standard specifies the air interface of fixed Broadband Wireless Access (BWA) system
More informationTroubleshooting Common Wi-Fi Problems
Troubleshooting Common Wi-Fi Problems It just has to work! Tom Resman - NetScout IT Professional Wi-Fi Trek 2016 What Wi-Fi Complaints Do You Typically Get? The Wi-Fi is too slow I keep getting disconnected
More informationCSCD 433/533 Advanced Networking
CSCD 433/533 Advanced Networking Lecture 6 Wireless LAN Components and Characteristics Winter 2017 Some Material in these slides from J.F Kurose and K.W. Ross All material copyright 1996-2007 1 Introduction
More informationLong Distance Wireless Communication. Principally satellite communication:
Long Distance Wireless Communication Principally satellite communication: Uplink/Downlink Footprint LOS (line of sight) communication satellite base station is relay Effective for broadcast Limited bandwidth
More information